1/23. Dopaminergic dysfunction in midbrain dystonia: anatomoclinical study using 3-dimensional magnetic resonance imaging and fluorodopa F 18 positron emission tomography.OBJECTIVE: To determine the role of damage to neuronal systems, especially the dopaminergic system, in patients with symptomatic dystonia and mesencephalic lesions. DESIGN: Stereotaxic magnetic resonance imaging analysis and positron emission tomography after the administration of fluorodopa F 18. patients: Of a group of 48 patients with unilateral dystonia following a stroke, 7 patients with a well-defined midbrain lesion were selected. RESULTS: All patients had unilateral dystonic posture of an upper extremity and cerebellar dysmetria or hypotonia. Cerebellar tremor was present in 1 patient. Two patients had resting and postural tremor, which showed a marked improvement with treatment with levodopa. In patients with dystonia only, dopaminergic lesions were mostly confined to the ventromesial mesencephalon and red nucleus area, including the substantia nigra and nigrostriatal and cerebellothalamic fibers. dystonia was severe and did not resolve with time in patients with lesions involving the nigrostriatal pathway, and the degree of dopaminergic denervation revealed by positron emission tomography was correlated with the severity of dystonia. In patients with resting and postural tremor, lesions of the dopaminergic structures were larger and located more laterally and dorsally in the pars compacta, the perirubral and retrorubral areas, and extending to the central tegmental tract. CONCLUSIONS: Dopaminergic dysfunction plays a role in the occurrence and severity of midbrain dystonia, and additional lesions to dopaminergic neurons in the perirubral and retrorubral areas result in tremor that responds to levodopa treatment.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
2/23. How broad is the phenotype of Hallervorden-Spatz disease?magnetic resonance imaging (MRI) has enabled ante mortem diagnosis of Hallervorden Spatz disease (HSD). Childhood-onset cases are the most common type and usually present with progressive dystonia and dementia. The duration of illness is 15 to 20 years, leading to death. Presentation in adulthood and infancy have also been reported, however again the progression is usually inexorable. We present a 30-year-old woman who developed cognitive and motor developmental delay from the age of 8 months. There was further cognitive decline in her late teenage years with seizures and then more recent motor decline with dystonia. The imaging appearance was of iron deposition in the globus pallidus and substantia nigra leading to a diagnosis of HSD. The increased availability of MRI has allowed more cases of HSD to be diagnosed in life but as our case illustrates classification of the disease may need to be further examined.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
3/23. Neuropathology of a case of dopa-responsive dystonia associated with a new genetic locus, DYT14.Detailed autopsy findings are reported for a patient with dopa-responsive dystonia genetically related to the dopa-responsive dystonia locus DYT14 on chromosome 14q13. substantia nigra and locus ceruleus showed a normal abundance of severely hypomelanized dopaminergic neurons and no Lewy body. In the nigra, the reduction of melanin pigment was found to be asymmetric between the two sides and uneven within neurons, and the lateral aspect of the nigra appeared more affected than the medial, in a pattern similar to the neuronal loss in PD. Dopa-responsive dystonia has a unique neuropathologic signature that seems to be independent of its genotype.- - - - - - - - - - ranking = 3keywords = nigra (Clic here for more details about this article) |
4/23. Hallervorden Spatz disease.A nine-month-old infant presented with fever and loss of milestones. Examination revealed intermittent rigidity and dystonic movements. magnetic resonance imaging (MRI) shows decreased signal intensity in globus pallidus and substantia nigra, indicative of iron deposition, suggesting Hallervorden Spatz Disease. The dopamine-neuromelanine system has been postulated to be the possible pathogenesis. Gene mapping has located the defect to be in the coding sequence of a gene called PANK-2. prenatal diagnosis is possible. The case is reported because of its rarity and early presentation.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
5/23. Dopa-responsive dystonia with depigmentation of the substantia nigra and formation of lewy bodies.The patient, who died at 23 years of age, was first diagnosed when she was 12 year old as having a dopa-responsive dystonia with decreased concentrations of monoamine metabolites in the cerebrospinal fluid. Also the concentrations of other neurotransmitters including somatostatin, substance p and metenkefalin were lowered indicating a more widespread damage of the cerebral neurotransmitter systems. At autopsy the brain was essentially intact except for pronounced gliosis and extreme loss of melanotic nerve cells in the substantia nigra. Several remaining nerve cells showed the presence of lewy bodies.- - - - - - - - - - ranking = 5keywords = nigra (Clic here for more details about this article) |
6/23. Hereditary spastic dystonia with Leber's hereditary optic neuropathy: neuropathological findings.Neuropathological findings in a 59-year-old male case of hereditary spastic dystonia with Leber's hereditary optic atrophy included: marked depletion of myelinated nerve fibres in the posterior funiculi, corticopontine tracts and striatum; practically complete neuronal depletion in the putamen and lateral part of the caudate, and mild cell loss in the substantia nigra. The putamina had changed into a spongy fibrillary scar, the pallidal fibres and laminae were practically all degenerated. Moreover, there was generalised mild fibre degeneration of the white matter. The optic nerve showed marked, predominantly central, loss of nerve fibres with demyelination.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
7/23. Smothering dystonia in a patient with oromandibular dystonia.A case report is presented of a patient with pathologically confirmed striatonigral degeneration who experienced episodic syncope as a result of oromandibular dystonia obstructing inhalation through her mouth and nose.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
8/23. Cyanide-induced akinetic rigid syndrome: clinical, MRI, FDG-PET, beta-CIT and HMPAO SPECT findings.A 35-year-old female ingested a lethal dose of potassium cyanide in a suicide attempt. She survived following antidote therapy and intensive care. Following artificial coma she presented with an agitative state for several days followed by akinetic mutism, buccofacial and ideomotoric aphasia. Severe rigid-akinetic syndrome, dysarthria, dysphagia and generalized dystonia developed weeks later. MRI revealed lesions in the caudate and lentiform nuclei, precentral cortex, and cerebellum. SPECT by [123-I] 2 beta-carbomethoxy-3-beta-(4-iodophenyl)-Tropan on two occasions revealed progressive loss of dopamine transporter suggestive of nigral neuronal apoptosis. Striatal and frontal hypometabolism and hypoperfusion were found by FDG-PET and HMPAO SPECT.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
9/23. New pathologic observations in juvenile onset parkinsonism with dystonia.A patient with hereditary juvenile onset parkinsonism with dystonia died at age 39. There were lewy bodies and regionally selective neuronal damage in the substantia nigra pars compacta. These changes closely resemble those seen in Parkinson's disease, and emphasize the selective vulnerability of the ventral tier of the pars compacta in these degenerations.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
10/23. Motor control in childhood onset dopa-responsive dystonia (Segawa syndrome).To elucidate the pathophysiological features of childhood onset dopa-responsive dystonia (DRD) we used a variety of quantitative analysis techniques to evaluate aspects of reflex- and voluntary motor control in two brothers with this disorder. The observed patterns were compared with those obtained in patients with adult onset Parkinson's disease (PD) and Huntington's disease (HD). In both brothers onset of the disease was in the first decade. Both responded either to treatment with L-Dopa or a combination of L-Dopa with trihexiphenidyl. Neurophysiological studies revealed slowing of different upper extremity voluntary motor activities and a low frequency postural tremor similar to results in other basal ganglia disorders including PD. In contrast to adult onset PD, fastest isometric voluntary index finger contractions did not show the typical kinetic tremor oscillations superimposed on the force trajectories. Also, different to adult PD, no impairment of stance regulating reflexes or saccadic and smooth pursuit eye movements was found in DRD. Magnetoelectrical stimulation of motor cortex showed normal efferent cortical spinal activity. Data indicate that like in other basal ganglia diseases slowing of voluntary motor activity is also a constant feature in DRD. DRD patients show, however, a clear difference to the pattern of motor abnormalities obtainable in PD. Both the pattern of motor control abnormalities is different, and the longlasting effect. In contrast to PD the pathophysiological mechanism in DRD possibly involves a lack of maturation of dopaminergic substantia nigra neurons rather than a degenerative process.- - - - - - - - - - ranking = 1keywords = nigra (Clic here for more details about this article) |
| | Next -> |